1. Field of the Invention
The present invention relates to a stand for supporting a monitor, and more particularly, to a monitor stand with tilt and height adjustment, and capable of preventing an “auto lift up” phenomenon that occurs when the monitor is tilted past a predetermined angle, due to a change in the acting direction of the monitor's weight.
2. Description of the Related Art
Generally, flat panel monitors such as liquid crystal display devices (LCD) require stands for supporting the monitors on a desk or table for use. Such stands have a hinge assembly interposed between the rear of the monitor and the stand to allow a user to adjust the monitor to a desired angle.
Recently, monitor stands have been developed to adjust not only the tilt angle, but also the height of the monitor, for added convenience.
Referring to FIG. 1, a monitor stand according to the related art will be described in detail.
As shown in FIGS. 1 and 2, a monitor stand according to the related art includes a stand top 4 installed to raise and lower the monitor 1, a stand body 2 pivotably supporting the stand top 4, and a base 3 for supporting the stand body 2 on a desk or other flat surface.
When a user grasps the upper or lower portion of the monitor 1 and pulls it forward, the stand top 4 pivots about the upper hinge 5 to adjust the tilt angle of the monitor 1.
In order to support the monitor 1, a spiral spring (not shown) that provides an elastic force in an upward direction equal to the weight W of the monitor 1, is provided inside the stand top 4. The spiral spring provides a uniform elastic force F to support the monitor 1 in an upward direction, regardless of its deformed state.
Accordingly, after the user moves the monitor 1 upwards or downwards with respect to the stand 4 and releases the force applied to the monitor 1, the monitor 1 maintains its current position due to the tension of the spiral spring (not shown) and the friction between components. Height adjusting of the monitor 1 is thus accomplished.
The lower portion of the stand body 2 is pivotably coupled to the base 3 with a lower hinge 6 interposed therebetween.
However, as shown in FIG. 2, in the above configuration of a monitor stand according to the related art, when a user pivots the monitor 1 to the rear, and the tilt angle exceeds a predetermined angle (30° from a vertical line, for example), the weight W of the monitor 1 is divided, so that the equilibrium between the tension F of the spiral spring and component of force W1 in a sliding direction of the monitor 1 is lost.
That is, when the monitor 1 has pivoted by an angle θ with respect to a vertical line, the component of force W1 of the monitor weight W1 is W cos θ, and becomes less than the tension F of the coil spring, so that when the difference exceeds the friction between the components, an auto lift up of the monitor 1 occurs. Therefore, an adjustment of the monitor to the height desired by the user does not occur. In severe cases, auto lift up of the monitor may cause it to collide with another object, causing a user unpleasantness.